1. Technical Field
The present invention relates to a method of fabricating a flexible device, and more particularly to a method of fabricating a flexible device, which enables an electronic, photoelectronic or energy device including a display to be reliably manufactured on a plastic substrate and also which enables a plastic substrate formed on a carrier plate to be easily separated from the carrier plate without an additional separation process thus facilitating the fabrication of the device.
2. Description of the Related Art
Recently, thorough research into flexible devices to develop electronic, photoelectronic, and energy devices including conventional flat panel displays, having environment-friendly properties, low power consumption, small sizes, lightweight, and flexibility, is ongoing. In order to enable flexible devices, a flexible substrate should be used as the most fundamental starting component. Typically useful candidates as the flexible substrate are metal foil, ultra-thin glass, plastic or a polymer film. In particular, the development of flexible devices using plastic or polymer films which may be easily applied to roll-to-roll processing and ink-jet printing and which have high price competitiveness is under very active study these days. Despite this being such an era and there being a technical demand, however, research into reliable flexible device fabrication processes for commercialization and mass production is still insufficient.
Methods of fabricating an electronic, photoelectronic or energy device including a display on a plastic film substrate are reported to be methods of fabricating devices directly onto freestanding plastic substrates, fabricating devices on plastic substrates using adhesives, a transfer process, and a laser release process. The case of fabricating devices directly onto freestanding plastic substrates is disadvantageous because the device is directly manufactured on a plastic substrate without a carrier plate, making it difficult to handle the fabricating process due to the absence of the carrier plate and to reliably manufacture the device due to severe deformation of the plastic substrate. For this reason, the fabrication of a flexible device backplane using a carrier plate such as a glass plate or the like is recently regarded as typical, which includes attaching a plastic or polymer film substrate to such a carrier plate, forming a device on the film substrate and then removing the carrier plate. For example, the use of such a carrier plate is disclosed in Korean Unexamined Patent Publication No. 10-2006-0028537, which includes attaching a plastic substrate to a carrier plate using an adhesive, fabricating a device, and then removing the carrier plate. The case of fabricating devices on plastic substrates using adhesives makes it possible to comparatively fabricate a flexible device in such a reliable manner that the device is formed on the plastic substrate attached onto the carrier plate using an adhesive or adhesion tape and then the carrier plate is removed using an organic solvent or the like. In this case, however, the adhesive may be left behind, undesirably causing contamination, and also the additional separation process is inevitably performed attributed to the use of the organic solvent. Furthermore, in the case of the transfer process and the laser release process, a release method including adhering a plastic substrate to a carrier plate using an amorphous silicon based sacrificial layer, fabricating a device and then removing the carrier plate using a laser and a device transfer method including a similar process are respectively disclosed in PCT WO 2005/050754 A1 and IEEE TRANSACTION ON ELECTRON DEVICES, VOL. 49, NO. 8 (2002). However, these methods are problematic because the amorphous silicon sacrificial layer functioning to attach the plastic substrate should be provided, undesirably complicating the fabrication process. In particular, because a laser is used during the transfer and separation processes, the yield is undesirably reduced and the process cost is increased.